Working model of LlWRKY33-LlHSFA4-LlCAT2 module under Botrytis cinerea attack. When lily is infected with B. cinerea, LlWRKY33 is rapidly induced and directly activate the expression of LlHSFA4 and LlCAT2 by binding to their promoters. Notably, LlHSFA4 could also directly bind to the HSE on the promoter of LlCAT2 and activate its expression. LlCAT2, a ROS scavenging enzyme, acts as a common target of LlWRKY33 and LlHSFA4 to prevent cell death caused by ROS accumulation to confer resistance to B. cinerea in lily.